• 제목/요약/키워드: holomorphic sectional curvature

검색결과 31건 처리시간 0.024초

KÄHLER SUBMANIFOLDS WITH LOWER BOUNDED TOTALLY REAL BISECTIONL CURVATURE TENSOR II

  • Pyo, Yong-Soo;Shin, Kyoung-Hwa
    • 대한수학회논문집
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    • 제17권2호
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    • pp.279-293
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    • 2002
  • In this paper, we prove that if every totally real bisectional curvature of an n($\geq$3)-dimensional complete Kahler submanifold of a complex projective space of constant holomorphic sectional curvature c is greater than (equation omitted) (3n$^2$+2n-2), then it is totally geodesic and compact.

CONNECTIONS ON ALMOST COMPLEX FINSLER MANIFOLDS AND KOBAYASHI HYPERBOLICITY

  • Won, Dae-Yeon;Lee, Nany
    • 대한수학회지
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    • 제44권1호
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    • pp.237-247
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    • 2007
  • In this paper, we establish a necessary condition in terms of curvature for the Kobayashi hyperbolicity of a class of almost complex Finsler manifolds. For an almost complex Finsler manifold with the condition (R), so-called Rizza manifold, we show that there exists a unique connection compatible with the metric and the almost complex structure which has the horizontal torsion in a special form. With this connection, we define a holomorphic sectional curvature. Then we show that this holomorphic sectional curvature of an almost complex submanifold is not greater than that of the ambient manifold. This fact, in turn, implies that a Rizza manifold is hyperbolic if its holomorphic sectional curvature is bounded above by -1.

LOWER HOUNDS ON THE HOLOMORPHIC SECTIONAL CURVATURE OF THE BERGMAN METRIC ON LOCALLY CONVEX DOMAINS IN $C^{n}$

  • Cho, Sang-Hyun;Lim, Jong-Chun
    • 대한수학회보
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    • 제37권1호
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    • pp.127-134
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    • 2000
  • Let $\Omega$ be a bounded pseudoconvex domain in$C^{n}$ with smooth defining function r and let$z_0\; {\in}\; b{\Omega}$ be a point of finite type. We also assume that $\Omega$ is convex in a neighborhood of $z_0$. Then we prove that all the holomorphic sectional curvatures of the Bergman metric of $\Omega$ are bounded below by a negative constant near $z_0$.

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SOME INEQUALITIES ON TOTALLY REAL SUBMANIFOLDS IN LOCALLY CONFORMAL KAEHLER SPACE FORMS

  • Alfonso, Carriazo;Kim, Young-Ho;Yoon, Dae-Won
    • 대한수학회지
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    • 제41권5호
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    • pp.795-808
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    • 2004
  • In this article, we establish sharp relations between the sectional curvature and the shape operator and also between the k-Ricci curvature and the shape operator for a totally real submanifold in a locally conformal Kaehler space form of constant holomorphic sectional curvature with arbitrary codimension. mean curvature, sectional curvature, shape operator, k-Ricci curvature, locally conformal Kaehler space form, totally real submanifold.

C12-SPACE FORMS

  • Gherici Beldjilali;Nour Oubbiche
    • 대한수학회논문집
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    • 제38권2호
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    • pp.629-641
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    • 2023
  • The aim of this paper is two-fold. First, we study the Chinea-Gonzalez class C12 of almost contact metric manifolds and we discuss some fundamental properties. We show there is a one-to-one correspondence between C12 and Kählerian structures. Secondly, we give some basic results for Riemannian curvature tensor of C12-manifolds and then establish equivalent relations among 𝜑-sectional curvature. Concrete examples are given.